It's a Wednesday night, and my boyfriend and I are drinking wine and making out in the back booth of a dimly lit bar. It feels like nothing else in the world exists… until my phone vibrates.

"It's my husband. The kids are in bed," I say, then put my phone in my purse and pull my boyfriend toward me. I spend half a second staring at the diamond on my engagement ring before hiding my hand from my sight line. It's not a secret that I'm married, but it's also not something I want to think about right now.

Am I a horrible person? Without context, I know I soundhorrible. But in my marriage, having affairs works. My husband and I don't talk about it. But I'm certain our don't-ask-don't-tell rule is what has allowed our marriage to last as long as it has.

Notice that I didn't say we're in an open marriage—we're not. An open marriage is transparent, with agreed-upon rules and an understanding of what both parties will and will not do with others. My marriage is opaque. I recognize what Frank and Claire Underwood have in House of Cards, although I like to think my husband and I aren't as soulless as their characters. But there are similarities: We know the other has secrets, but we don't care to find out more. It's an attitude people think of as very French—the idea that you can have an affair and a healthy marriage. Quite honestly, it works. But that doesn't mean it's easy.

When Dave* and I met in our late 20s, I knew that he was a player. So was I. We also had chemistry beyond anything else I'd ever experienced. We just got each other. When I was with him, I could be myself. He was the only boyfriend I've ever told the truth to about how many men I'd slept with, because I believed that no matter what I said, he'd never judge me. He also never seemed to get jealous.

After about six months of late-night booty calls, Dave and I settled into a proper relationship and started calling each other boyfriend and girlfriend. At first, it was incredibly volatile. After not hearing from him for an evening, I'd go ballistic. He'd refuse to engage, saying he had nothing to apologize for. We yelled about cheating—he'd do it, I'd do it, we'd be furious with each other. But eventually, I realized this dynamic wouldn't change. One of us would always act out ifcheating was against the rules.

But what if it wasn't? What if we both admitted that, yes, we were sometimes tempted, and that sometimes we acted on that temptation? I think I was the one who brought it up over dinner one night, just after we'd moved in together. I told him that I'd no longer ask questions, that I didn't want to know. He said he'd do the same. We reaffirmed that we loved each other, and that wouldn't change. And then, without drawing up any official rules, we embarked on our anything-but-traditional relationship.

We got married seven years ago and now have two sons, ages four and nearly two. The arguments started up again during my first pregnancy. I was pretty sure Dave was sleeping with someone else while I was stuck at home. Before, I felt we could both have our cake and eat it, too, but the lastthing I wanted to do when I was pregnant was seek out an affair. It seemed tawdry and gross, and I resented the fact that all my husband had to do was slip off his ring and he'd look single. Meanwhile, I was huge, hormonal, and knew my husband was cheating on me. When I told him how I felt, he broke off his side situation.

Toward the last trimester of my pregnancy, Dave was amazing. He was home every night, did everything around the house, and was 100-percent there for me—but I still felt resentful and like I'd gotten the short end of the stick.

A few months after our son was born, I quickly got into a relationship with a former coworker. It wasn't great—I really would have rather been at home with my son, and I felt I was punishing myself for my husband's behavior during my pregnancy. I liked my coworker, but I know I pushed us into romantic territory fast because I wanted to feel desired. My husband and I had some huge fights during that time, and we both uttered the word "divorce." But deep down, neither of us wanted that. We love each other. We also seriously like other people.

I ended my affair, and for the next six months or so, my husband and I recommitted to our marriage and our family. And once we settled into a comfortable rhythm of life with a baby, we both began relaxing into our old routines. He came home late. I flirted with men when I went out with my single girlfriends. And little by little, we reached the point we're at now, where both of us occasionally have affairs on the side but always come home to each other.

Normally, the guys I have affairs with are men I meet through my job—I travel a lot—as an event coordinator, at parties, through friends of friends, or even old flames I've reconnected with on Facebook. I've always been the type of person who gets physical fast, and being married hasn't changed that. I don't keep my marriage a secret from the guys I date—I don't take off my rings and I mention my husband and kids in front of them—but I also don't make it an issue. Often, they're cheating as well, and I feel there's an unspoken code about what we do and don't discuss.

Right now, I'm 40 and my husband is 38, and I do wonder how long we can keep this up. I don't want to actively seek outaffairs. I feel like my work, thanks to all those business trips, has made it easy to fall into them without doing much damage to my everyday life.

I haven't said "I love you"to anyone else since I met my husband, and I do sometimes wonder how my husband feels toward the women he meets. I know—and hope he knows—that very few women would put up with a similar type of relationship, and I think that understanding is part of the bedrock of our bond.

When I say I'm going out, he tells me to have a good time. He'll send texts, but I'm not obligated to respond. I text him if I won't be coming home (which, truthfully, happens very rarely since we've had kids), and I always have safe sex. Sometimes, I truly am just going out for a glass of wine with a girlfriend, but I like the intrigue that I couldbe meeting a man. I'm pretty sure when he goes out, it's to meet a woman—or women. I think I can tell when he is in a serious "relationship"—he'll wear the same cologne and leave with a book tucked under his arm to give her—versus when he may be casually meeting someone for sex. He also travels a lot for work, and I don't know what he does while he's gone. It's harder when I think something is going on while we're both in town.

The more I think about it, the less okay I am with our lifestyle, so I've become pretty good at shutting down that part of my brain. Because truth be told, I doworry that Dave might fall in love with someone else. That's why when I see his secret smiles or notice him spending tons of time texting, I step it up on my end, asking him to be home on a certain night and initiating sex. I remind him how much I love him and how much our marriage means to me.

I won't talk to him about it directly, though, because while it's terrifying to imagine my husband leaving me, I know it's possible. But that's true in any relationship, and I don't think the fact that my husband can sleep with other women makes him any more likely to fall in love with one of them. I believe that if you love something, you let it go, and if it's yours, it'll come back to you. Of course, that's easier said than done, but it's something I try to remind myself. And so far, he's come back every time.

And for that matter, so have I. I've had three relationships since Dave and I got married. Even though I was very fond of each of those men, I didn't want to be married to them. The affairs aren't my real life. They're fancy cocktails and tiny plates and falling asleep without the whooshing sound of a baby monitor. And they make me that much happier for the family I do have.

I've often thought about what would happen if Dave and I were to be more transparent, but I don't think it would work. We live in a society where monogamy is everything, and it's hard to explain that you can love having sex with multiple people but still only loveone person. We both knowthis, but if we tried to put our behavior into words, I'm afraid we'd say things we'd regret. The closest we came was when I got an abnormal Pap smear result. The retest came back normal, but it did give me pause and make me wonder how safe what we were doing was, physically and emotionally. Dave and I had a serious talk about safety, but spoke mostly in the abstract—about things that mighthave happened in the past—and came down to the rule that we will always have safe sex with other people.

I'm not sure what will happen as our sons get older—or, for that matter, what will happen as we get older. For now, our personal decisions don't affect our sons' lives, but if that changes—if the kids start asking questions, or if one of us starts missing major milestones because we're spending too much time out of the house—then Dave and I may need to lay everything on the table and reconfigure the dynamics of our relationship. We also may find that playing with fire isn't as much fun. Already, I find my priorities have shifted so much in the past decade—most of the time, there's nowhere else I'd rather be than home on the floor, playing with my son and husband.

But that's most of the time. Once every few weeks, there's something magical about being out with a man who's not my husband. Just call it the secret spark that keeps my marriage alive.